Conventionally, a layered clay mineral having a large aspect ratio (size/thickness of a particle) has been converted into thin-layered one and is homogeneously dispersed in a resin to improve resin properties such as mechanical strength, heat resistance, and gas barrier properties. Moreover, the effect of improving the above properties is more advantageous as the aspect ratio increases (e.g., see Patent Document 1). There is disclosed a composite material containing a layered silicate salt and a plasticiser, wherein the layered silicate salt is finely dispersed. Therein, a means of finely dispersing a layered silicate salt such as a smectite-based clay mineral by organically treating interlayers of the layered silicate salt with a cationic surfactant (a quaternary ammonium salt or the like) is shown (see Patent Document 2). Furthermore, as a composite material wherein a carbonaceous material is dispersed in an order of nanometer size, there is disclosed a composite resin composition composed of a resin and a layered carbon dispersed in the resin, wherein the layered carbon is modified or subjected to a solubilization treatment (see Patent Document 3).    Patent Document 1: JP-A-10-330534    Patent Document 2: JP-A-2001-26724    Patent Document 3: JP-A-2003-268245